Randomized, Multicentre Study of the Efficacy and Tolerance of Azithromycin versus Clarithromycin in the Treatment of Adults with Mild to Moderate Community-Acquired Pneumonia

Abstract

Adults with mild to moderate community-acquired pneumonia were treated with azithromycin (500 mg once daily for 3 days) or clarithromycin (250 mg twice daily for 10 days) and clinically assessed between days 3 and 7 and days 12 and 16. Patients classified as improved at the day 12–16 visit were also evaluated between days 19 and 23. Two hundred three patients were treated (101 with azithromycin, 102 with clarithromycin). A satisfactory clinical response was recorded at the end of therapy in 83 of 88 (94%) evaluable azithromycin-treated and 84 of 88 (95%) evaluable clarithromycin-treated patients (P=0.518). At day 19–23, only one patient in each treatment group had relapsed. Thirty-one of 32 (97%) pathogens isolated from patients in the azithromycin group were eradicated, compared with 32 of 35 (91%) isolated from clarithromycin patients. In all patients with atypical pneumonia, the clinical response was satisfactory at follow-up. Incidences of treatment-related adverse events were similar for the two groups (P=0.815). Two (2%) clarithromycin patients discontinued therapy due to severe treatment-related adverse events; none in the azithromycin group did. This study shows that a 3-day, once-daily course of azithromycin is as clinically effective and well tolerated as a 10-day, twice-daily course of clarithromycin in the treatment of mild to moderate community-acquired pneumonia.